package com.cyh.forum.interceptor;

import com.cyh.forum.config.AppConfig;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

@Component
public class LoginInterceptor implements HandlerInterceptor {

    @Value("${bit-forum.login.url}")
    private String defaultURL;

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //  获取session对象
        HttpSession session = request.getSession(false);
        //  校验session是否有效
        if (session != null && session.getAttribute(AppConfig.USER_SESSION) != null){
            //  用户为登录状态,校验通过
            return true;
        }
        //  校验 URL
        if (!defaultURL.startsWith("/")){
            defaultURL = "/" + defaultURL;
        }

        //  校验不通过,跳转到登录界面
        response.sendRedirect(defaultURL);
        //  中断流程
        return false;
    }
}
